Fastest-Spinning Exoplanet Beta Pictoris b- Explained With Complete Infographic

Planets usually attain their rotation when they are formed, taking angular momentum from the influences that form them. There is a connection among the total mass of a planet and the roral speed of its rotation, excluding where tidal forces have decelerated planets and made their days longer.

         Diagram of day length on various planets.
Source SPACE.com: All about our solar system, outer space and exploration.